<template>
  <div class="pswp" tabindex="-1" role="dialog" aria-hidden="true">

    <!-- Background of PhotoSwipe.
         It's a separate element as animating opacity is faster than rgba(). -->
    <div class="pswp__bg"></div>

    <!-- Slides wrapper with overflow:hidden. -->
    <div class="pswp__scroll-wrap">

      <!-- Container that holds slides.
          PhotoSwipe keeps only 3 of them in the DOM to save memory.
          Don't modify these 3 pswp__item elements, data is added later on. -->
      <div class="pswp__container">
        <div class="pswp__item"></div>
        <div class="pswp__item"></div>
        <div class="pswp__item"></div>
      </div>

      <!-- Default (PhotoSwipeUI_Default) interface on top of sliding area. Can be changed. -->
      <div class="pswp__ui pswp__ui--hidden">

        <div class="pswp__top-bar">

          <!--  Controls are self-explanatory. Order can be changed. -->

          <div class="pswp__counter"></div>

          <button class="pswp__button pswp__button--close" title="Close (Esc)"></button>

          <button class="pswp__button pswp__button--share" title="Share"></button>

          <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button>

          <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button>

          <!-- Preloader demo http://codepen.io/dimsemenov/pen/yyBWoR -->
          <!-- element will get class pswp__preloader--active when preloader is running -->
          <div class="pswp__preloader">
            <div class="pswp__preloader__icn">
              <div class="pswp__preloader__cut">
                <div class="pswp__preloader__donut"></div>
              </div>
            </div>
          </div>
        </div>

        <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap">
          <div class="pswp__share-tooltip"></div>
        </div>

        <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)">
        </button>

        <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)">
        </button>

        <div class="pswp__caption">
          <div class="pswp__caption__center"></div>
        </div>

      </div>

    </div>

  </div>
</template>

<script>
import PhotoSwipe from 'photoswipe/dist/photoswipe'
import UI from 'photoswipe/dist/photoswipe-ui-default'

export default {
  name: 'photo-swipe',
  methods: {
    open (index, list, options = {
      captionEl: false,
      fullscreenEl: true,
      history: false,
      shareEl: false,
      tapToClose: true,
      bgOpacity: 0.7
    }) {
      options.index = index
      options.getThumbBoundsFn = function(index) {
        // find thumbnail element
        let thumbnail = list[index].target

        // get window scroll Y
        let pageYScroll = window.pageYOffset || document.documentElement.scrollTop
        // optionally get horizontal scroll

        // get position of element relative to viewport
        let rect = thumbnail.getBoundingClientRect()

        // w = width
        return {x:rect.left, y:rect.top + pageYScroll, w:rect.width}
      }
      let width = window.innerWidth
      let height = window.innerHeight
      list.forEach((item) => {
        let ratio = item.w / item.h
        if (width > height) {
          item.w = height * ratio
          item.h = height
        } else {
          item.h = width / ratio
          item.w = width
        }
      })
      this.photoswipe = new PhotoSwipe(this.$el, UI, list, options)
      this.photoswipe.init()
    },
    close () {
      this.photoswipe.close()
    }
  }
}
</script>

<style>
@import '~photoswipe/dist/photoswipe.css';
@import '~photoswipe/dist/default-skin/default-skin.css';
</style>